code: def test_overlay_heatmap(boxrgba):
      overlay = _overlay_heatmap(boxrgba, boxrgba)
      assert_pixel_by_pixel_equal(overlay, boxrgba)
  
imports: import pytest
  import numpy
  from eli5.base import Explanation, TargetExplanation
  from eli5.formatters.image import format_as_image, heatmap_to_image, expand_heatmap, _validate_heatmap, _update_alpha, _cap_alpha, _overlay_heatmap
  from .utils_image import assert_pixel_by_pixel_equal
label_desc: Use image node_id 17 for calling a global function with example usage: test_overlay_heatmap(boxrgba) without return types